1. Field of the Invention
This invention relates to a device for stabilizing the current of X-ray tube in an X-ray photographing apparatus.
2. Prior Art
When the time required for photographing by an X-ray photographing apparatus is relatively long, it is necessary for the apparatus to make constant the current in the X-ray tube during photographing in order to uniform the density of an X-ray photograph taken, and it is a common practice for the apparatus to be integrally equipped with a constant-voltage transformer or the like to adjust supply voltage fluctuations. But the conventional apparatus was not free from disadvantages such as variations in the X-ray tube current due to deterioration in each element constituting the X-ray tube in proportion to the number of years during which the tube was used, reductions in the strength of X-rays due to the charge collected on the tube wall by effect of time during production of X-rays and to reductions in the velocity of electron beams made by the charge thus collected and to resultant gradual decrease in the tube current along with the progress of photographing, and so on.